The instant invention is directed to a fiber web forming apparatus which includes an arrangement for delivering chemical agents, preferably in powder form, into the fiber mixing chamber.
The instant arrangement is for forming a stable fiber web having high loft and high resilience. The arrangement includes a cabinet receiving opened and blended fibers and a fiber web forming chute which receives the opened and blended fibers from the cabinet. The forming chute including a first and second wall with fiber contacting elements which engage the fibers and assist in urging them through the fiber forming chute and out its exit in an evenly distributed condition forming a fiber web. The fiber contacting elements include a fiber inter-engaging device associated with at least one of the first and second walls. The inter-engaging device acts on at least the outer fibers adjacent to at least one of the first and second walls to cause these fibers to inter-engage creating a stable outer surface on the fiber web being formed. A fiber web so constructed will better maintain its formed configuration during transport to further processing.
The fiber inter-engaging device may comprise a heating element which when contacting the outer fibers causes adjacent ones to fuse together. There may be a pair of these heating rolls located adjacent the exit in opposing relationship.
The fiber inter-engaging device is formed as at least a portion of the first and second walls.
The fiber inter-engaging device may comprise a needle bed or a pair of opposed needle beds which operate within the chute along at least one of the first and second walls.
The arrangement may include an air distribution system which delivers an air flow into the fiber-forming chute for assisting in the distribution and movement of the fibers within the forming chute. A distributor may be associated with the air distribution system which is operative to add chemical agents to the air flow for distribution throughout the fibers during formation of the fiber web.
Alternatively, the arrangement may include a distributor for adding the chemicals to a feed chute above the mixing chamber. In this arrangement, the beater roll acts to throw the fibers into the chemical agent being fed into the mixing chamber by a feed roll. The distribution in this arrangement may include a chemical agent supply, a delivery belt and a vertical feed chute.
The arrangement may include a conveyor system adjacent the chute exit. The fiber inter-engaging device may be arranged to be adjacent one end of the conveyor system. The fiber inter-engaging system may comprise a heating member for heating at the outer fibers of the fiber web passing over the conveyor causing adjacent fibers to fuse. The heating member may comprise a pair of heating rolls.
The fiber-contacting element may include a packing belt which forms at least a part of one of the first and second walls. Also, the fiber-contacting element may include a vibrating plate forming at least a part of one of the first and second walls. There may be a compression roll adjacent the exit which is heated. The heated compressor roll acts to compress and to fuse the outer fibers of the fiber web.